Facile Synthesis of Dual-Network Polymer Hydrogels with Anti-Freezing, Highly Conductive, and Self-Healing Properties

• Published in: Materials Vol. 17; no. 6; p. 1275
• Main Authors: Jin, Yuchen, Zhao, Lizhu, Jiang, Ya, Zhang, Xiaoyuan, Su, Zhiqiang
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 10.03.2024; MDPI
• Subjects: Acids; Acrylamide; Acrylic acid; Biosensors; Carboxymethyl cellulose; Chemical bonds; Chemical synthesis; Competitive materials; conductivity; dual-network hydrogels; Electric properties; Electrical conductivity; Electrical resistivity; Electrolytes; Ferric chloride; Freezing; Frost resistance; Hydrogels; Hydrogen bonds; Mechanical properties; Melting points; Modulus of elasticity; Polymerization; Polymers; Saline solutions; self-healing; Sensors; Sodium; Swelling; swelling resistance; Temperature; China; dual-network hydrogels; frost resistance; conductivity; swelling resistance; self-healing
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma17061275

We report the synthesis of poly(acrylamide-co-acrylic acid)/sodium carboxy methyl cellulose (PAMAA/CMC-Na) hydrogels, and subsequent fabrication of dual-network polymer hydrogels (PAMAA/CMC-Na/Fe) using as-prepared via the salt solution (FeCl ) immersion method. The created dual-network polymer hydrogels exhibit anti-swelling properties, frost resistance, high conductivity, and good mechanical performance. The hydrogel swells sightly when immersed in solution (pH = 2~11). With the increase in n :n , the modulus of elasticity experiences a rise from 1.1 to 1.6 MPa, while the toughness undergoes an increase from 0.18 to 0.24 MJ/m . Furthermore, the presence of a high concentration of CMC-Na also contributes to the enhancement of mechanical strength in the resulting hydrogels, ascribing to enhanced physical network of the hydrogels. The minimum freezing point reaches -21.8 °C when the CMC-Na concentration is 2.5%, owing to the dissipated hydrogen bonds by the coordination of Fe with carboxyl (-COO ) in CMC-Na and PAMAA. It is found that the conductivity of the PAMAA/CMC-Na/Fe hydrogels gradually decreased from 2.62 to 0.6 S/m as the concentration of CMC-Na rises. The obtained results indicates that the dual-network hydrogels with high mechanical properties, anti-swelling properties, frost resistance, and electrical conductivity can be a competitive substance used in the production of bendable sensors and biosensors.